Add some comments and expand some method documentation

plugins/commands/serve/mappers/internal/graph/search.rb

@@ -281,6 +281,18 @@ module VagrantPlugins
             # applied. After the given block is executed, the value
             # vertices will have their original weights re-applied.
             #
+            # Since value vertices are identified by type, only
+            # one value of any type may exist in the graph. However,
+            # if the value is named, then multiple values of the same
+            # type may exist in the graph. For instance, with named
+            # values two strings could be provided, one named "local_path"
+            # and another named "remote_path". If a mapper function is
+            # only interested in the value of the "remote_path", it
+            # can include that name within its input definition. Then
+            # this method can be used to prefer the name string argument
+            # "remote_path" over the "local_path" named argument, or
+            # just a regular string value.
+            #
             # @param vertex [Vertex] source vertex
             # @param graph [Graph] graph to modify
             # @yieldparam [Graph] modified graph (passed instance, not a copy)

plugins/commands/serve/mappers/internal/graph/vertex.rb

@@ -43,19 +43,29 @@ module VagrantPlugins
               value
             end
 
+            # Determine if provided vertex is equivalent
+            #
+            # @param [Vertex]
+            # @return [Boolean]
             def ==(v)
               v.hash_code == hash_code
             end
             alias_method :eql?, :==
 
+            # Generate a hash for the given vertex. This is used
+            # to uniquely identify a vertex within a Hash.
+            #
+            # @return [Integer]
             def hash
               hash_code.to_s.chars.map(&:ord).sum.hash
             end
 
+            # @return [String]
             def to_s
               "<Vertex value=#{value} hash=#{hash_code}>"
             end
 
+            # @return [String]
             def inspect
               "<#{self.class.name} value=#{value} hash=#{hash_code}>"
             end